Description

Support for textures with negative values

This very small patch adds support for textures containing negative values (i.e. OpenEXR)

The problem with Blender was that during Contrast & Brightness adjustment values below zero were being clamped. The main advantage of this 'feature' is to have more flexibility when dealing with the deform modifier.

A check box to enable this new behavior was added below Brighness, Contrast & Saturation sliders. Default value is disabled, which is the old behavior. Enabling it will gray out saturation, since it doesn't make sense, and mathematically speaking because RGB->HSV->RGB conversion doesn't expect negative values.

Using SVN 48705 (Blender 2.63)

A Blend file with an OpenEXR image containing negative values is included for testing; also contains two screenshots to see show the difference between the patched version and a non-patched one.